Superconducting ceramic oxides (i.e., the IBM 1-2-3 superconductors) are perovskite ceramics and are a recent technological breakthrough with promising applications in a wide range of areas. Superconductors are materials which transmit electricity without significant resistive losses and can sustain high magnetic fields when cooled below their superconducting transition temperature, T.sub.c. The new class of superconducting ceramic oxides (sometimes also called superconducting mixed metal oxides or superconducting metal oxides) typically exhibit superconductivity at ambient pressure above 77.degree. K. (-321.degree. F.), the temperature of liquid nitrogen, which signifies the ability to prepare and maintain superconductive materials now in virtually any laboratory. Being superconductors at "high" temperatures is a tremendous advantage since the previously known superconductors only exhibited this property if they were cooled with liquid helium, which is expensive and difficult to handle.
Using superconducting ceramic oxides, it is often difficult to produce large, mechanically stable, complex shapes, or any stable shapes for that matter. Hence, commercial adoption of these superconductor ceramic oxides has been slower than the promise and potential foreseen when they were first discovered. The superconducting ceramic oxides are brittle, difficult to handle without damaging the ceramic (the materials lack glass formers and have low tensile strengths), and particularly difficult to form into a wire or fiber, the most desired form for high current applications. For small scale applications (such as for microcomponents for electronic devices) low current carrying superconducting ceramic oxides may be made in the form of single crystals. The technology for making large single crystals suitable for high current industrial, however, uses is not yet practical.
U.S. patent application Ser. No. 07/381,498, describes a method of manufacturing superconductive fiberformed ceramic composites which exhibit superconductivity at liquid nitrogen temperatures, which do not require high temperature consolidation of the superconducting metal oxide powder, and which can be produced in large complex shapes at relatively low cost.. The present application describes related perovskite fiberform ceramics or coated ceramics that substitute sols from the LaMnO.sub.3 -family for the superconductive sols earlier used. The family of LaMnO.sub.3 sols includes pure LaMnO.sub.3 sols and those sols doped with varying amounts of strontium or chromium or both. The dopants provide charge carriers to produce sols and corresponding ceramic oxides having tailorable electrical conductivities as reported by R. Koc in his Master's Thesis: "Structural, Sintering and Electrical Conductivity Studies of the LaCrO.sub.3 -LaMnO.sub.3 System, May 1986, University of Missouri-Rolla, incorporated by reference.